import base64js from 'base64-js';

/**
 * 国密SM4加密算法
 * @author wzk
 * @email 1216113487@qq.com
 * @company 中科软
 */
interface SM4Context {
	mode: number;
	isPadding: boolean;
	sk: number[];
}

class SM4 {
	public SM4_ENCRYPT = 1;
	public SM4_DECRYPT = 0;

	private SboxTable: number[] = [
		0xd6, 0x90, 0xe9, 0xfe, 0xcc, 0xe1, 0x3d, 0xb7, 0x16, 0xb6, 0x14, 0xc2, 0x28, 0xfb, 0x2c, 0x05, 0x2b, 0x67, 0x9a, 0x76, 0x2a, 0xbe, 0x04, 0xc3,
		0xaa, 0x44, 0x13, 0x26, 0x49, 0x86, 0x06, 0x99, 0x9c, 0x42, 0x50, 0xf4, 0x91, 0xef, 0x98, 0x7a, 0x33, 0x54, 0x0b, 0x43, 0xed, 0xcf, 0xac, 0x62,
		0xe4, 0xb3, 0x1c, 0xa9, 0xc9, 0x08, 0xe8, 0x95, 0x80, 0xdf, 0x94, 0xfa, 0x75, 0x8f, 0x3f, 0xa6, 0x47, 0x07, 0xa7, 0xfc, 0xf3, 0x73, 0x17, 0xba,
		0x83, 0x59, 0x3c, 0x19, 0xe6, 0x85, 0x4f, 0xa8, 0x68, 0x6b, 0x81, 0xb2, 0x71, 0x64, 0xda, 0x8b, 0xf8, 0xeb, 0x0f, 0x4b, 0x70, 0x56, 0x9d, 0x35,
		0x1e, 0x24, 0x0e, 0x5e, 0x63, 0x58, 0xd1, 0xa2, 0x25, 0x22, 0x7c, 0x3b, 0x01, 0x21, 0x78, 0x87, 0xd4, 0x00, 0x46, 0x57, 0x9f, 0xd3, 0x27, 0x52,
		0x4c, 0x36, 0x02, 0xe7, 0xa0, 0xc4, 0xc8, 0x9e, 0xea, 0xbf, 0x8a, 0xd2, 0x40, 0xc7, 0x38, 0xb5, 0xa3, 0xf7, 0xf2, 0xce, 0xf9, 0x61, 0x15, 0xa1,
		0xe0, 0xae, 0x5d, 0xa4, 0x9b, 0x34, 0x1a, 0x55, 0xad, 0x93, 0x32, 0x30, 0xf5, 0x8c, 0xb1, 0xe3, 0x1d, 0xf6, 0xe2, 0x2e, 0x82, 0x66, 0xca, 0x60,
		0xc0, 0x29, 0x23, 0xab, 0x0d, 0x53, 0x4e, 0x6f, 0xd5, 0xdb, 0x37, 0x45, 0xde, 0xfd, 0x8e, 0x2f, 0x03, 0xff, 0x6a, 0x72, 0x6d, 0x6c, 0x5b, 0x51,
		0x8d, 0x1b, 0xaf, 0x92, 0xbb, 0xdd, 0xbc, 0x7f, 0x11, 0xd9, 0x5c, 0x41, 0x1f, 0x10, 0x5a, 0xd8, 0x0a, 0xc1, 0x31, 0x88, 0xa5, 0xcd, 0x7b, 0xbd,
		0x2d, 0x74, 0xd0, 0x12, 0xb8, 0xe5, 0xb4, 0xb0, 0x89, 0x69, 0x97, 0x4a, 0x0c, 0x96, 0x77, 0x7e, 0x65, 0xb9, 0xf1, 0x09, 0xc5, 0x6e, 0xc6, 0x84,
		0x18, 0xf0, 0x7d, 0xec, 0x3a, 0xdc, 0x4d, 0x20, 0x79, 0xee, 0x5f, 0x3e, 0xd7, 0xcb, 0x39, 0x48,
	];

	private FK: number[] = [0xa3b1bac6, 0x56aa3350, 0x677d9197, 0xb27022dc];
	private CK: number[] = [
		0x00070e15, 0x1c232a31, 0x383f464d, 0x545b6269, 0x70777e85, 0x8c939aa1, 0xa8afb6bd, 0xc4cbd2d9, 0xe0e7eef5, 0xfc030a11, 0x181f262d, 0x343b4249,
		0x50575e65, 0x6c737a81, 0x888f969d, 0xa4abb2b9, 0xc0c7ced5, 0xdce3eaf1, 0xf8ff060d, 0x141b2229, 0x30373e45, 0x4c535a61, 0x686f767d, 0x848b9299,
		0xa0a7aeb5, 0xbcc3cad1, 0xd8dfe6ed, 0xf4fb0209, 0x10171e25, 0x2c333a41, 0x484f565d, 0x646b7279,
	];

	constructor() {}

	private GET_ULONG_BE(b: number[], i: number): number {
		return ((b[i] & 0xff) << 24) | ((b[i + 1] & 0xff) << 16) | ((b[i + 2] & 0xff) << 8) | (b[i + 3] & 0xff);
	}

	private PUT_ULONG_BE(n: number, b: number[], i: number): void {
		b[i] = (n >> 24) & 0xff;
		b[i + 1] = (n >> 16) & 0xff;
		b[i + 2] = (n >> 8) & 0xff;
		b[i + 3] = n & 0xff;
	}

	private SHL(x: number, n: number): number {
		return (x & 0xffffffff) << n;
	}

	private ROTL(x: number, n: number): number {
		return this.SHL(x, n) | (x >> (32 - n));
	}

	private sm4Lt(ka: number): number {
		const a: number[] = new Array(4);
		const b: number[] = new Array(4);
		this.PUT_ULONG_BE(ka, a, 0);
		b[0] = this.sm4Sbox(a[0]);
		b[1] = this.sm4Sbox(a[1]);
		b[2] = this.sm4Sbox(a[2]);
		b[3] = this.sm4Sbox(a[3]);
		const bb = this.GET_ULONG_BE(b, 0);
		return bb ^ this.ROTL(bb, 2) ^ this.ROTL(bb, 10) ^ this.ROTL(bb, 18) ^ this.ROTL(bb, 24);
	}

	private sm4F(x0: number, x1: number, x2: number, x3: number, rk: number): number {
		return x0 ^ this.sm4Lt(x1 ^ x2 ^ x3 ^ rk);
	}

	private sm4CalciRK(ka: number): number {
		const a: number[] = new Array(4);
		const b: number[] = new Array(4);
		this.PUT_ULONG_BE(ka, a, 0);
		b[0] = this.sm4Sbox(a[0]);
		b[1] = this.sm4Sbox(a[1]);
		b[2] = this.sm4Sbox(a[2]);
		b[3] = this.sm4Sbox(a[3]);
		const bb = this.GET_ULONG_BE(b, 0);
		return bb ^ this.ROTL(bb, 13) ^ this.ROTL(bb, 23);
	}

	private sm4Sbox(inch: number): number {
		const i = inch & 0xff;
		let retVal = this.SboxTable[i];
		if (retVal > 128) {
			retVal -= 256;
		}
		return retVal;
	}

	public sm4_setkey_enc(ctx: SM4Context, key: number[]): void {
		if (!ctx || !key || key.length !== 16) {
			throw new Error('Invalid context or key');
		}
		ctx.mode = this.SM4_ENCRYPT;
		this.sm4_setkey(ctx.sk, key);
	}

	public sm4_setkey_dec(ctx: SM4Context, key: number[]): void {
		if (!ctx || !key || key.length !== 16) {
			throw new Error('Invalid context or key');
		}
		ctx.mode = this.SM4_DECRYPT;
		this.sm4_setkey(ctx.sk, key);
		ctx.sk.reverse();
	}

	private sm4_setkey(SK: number[], key: number[]): void {
		const MK: number[] = [this.GET_ULONG_BE(key, 0), this.GET_ULONG_BE(key, 4), this.GET_ULONG_BE(key, 8), this.GET_ULONG_BE(key, 12)];
		const k: number[] = new Array(36);
		k[0] = MK[0] ^ this.FK[0];
		k[1] = MK[1] ^ this.FK[1];
		k[2] = MK[2] ^ this.FK[2];
		k[3] = MK[3] ^ this.FK[3];
		for (let i = 0; i < 32; i++) {
			k[i + 4] = k[i] ^ this.sm4CalciRK(k[i + 1] ^ k[i + 2] ^ k[i + 3] ^ this.CK[i]);
			SK[i] = k[i + 4];
		}
	}

	private padding(input: number[], mode: number): number[] {
		if (!input) return [];
		let p: number;
		if (mode === this.SM4_ENCRYPT) {
			p = 16 - (input.length % 16);
			const ret = input.slice();
			for (let i = 0; i < p; i++) {
				ret[input.length + i] = p;
			}
			return ret;
		} else {
			p = input[input.length - 1];
			return input.slice(0, input.length - p);
		}
	}

	private sm4_one_round(sk: number[], input: number[], output: number[]): void {
		const ulbuf: number[] = new Array(36);
		ulbuf[0] = this.GET_ULONG_BE(input, 0);
		ulbuf[1] = this.GET_ULONG_BE(input, 4);
		ulbuf[2] = this.GET_ULONG_BE(input, 8);
		ulbuf[3] = this.GET_ULONG_BE(input, 12);
		for (let i = 0; i < 32; i++) {
			ulbuf[i + 4] = this.sm4F(ulbuf[i], ulbuf[i + 1], ulbuf[i + 2], ulbuf[i + 3], sk[i]);
		}
		this.PUT_ULONG_BE(ulbuf[35], output, 0);
		this.PUT_ULONG_BE(ulbuf[34], output, 4);
		this.PUT_ULONG_BE(ulbuf[33], output, 8);
		this.PUT_ULONG_BE(ulbuf[32], output, 12);
	}

	public sm4_crypt_ecb(ctx: SM4Context, input: number[]): number[] {
		if (!input) throw new Error('Input is null');
		let data = input;
		if (ctx.isPadding && ctx.mode === this.SM4_ENCRYPT) {
			data = this.padding(data, this.SM4_ENCRYPT);
		}

		const bous: number[] = [];
		for (let i = 0; i < data.length; i += 16) {
			const ins = data.slice(i, i + 16);
			const out = new Array(16).fill(0);
			this.sm4_one_round(ctx.sk, ins, out);
			bous.push(...out);
		}

		let output = bous;
		if (ctx.isPadding && ctx.mode === this.SM4_DECRYPT) {
			output = this.padding(output, this.SM4_DECRYPT);
		}

		return output.map((v) => (v < 0 ? v + 256 : v));
	}

	public sm4_crypt_cbc(ctx: SM4Context, iv: number[], input: number[]): number[] {
		if (!iv || iv.length !== 16) throw new Error('IV error');

		let data = input;
		if (ctx.isPadding && ctx.mode === this.SM4_ENCRYPT) {
			data = this.padding(data, this.SM4_ENCRYPT);
		}

		const bous: number[] = [];
		let currentIv = [...iv];

		if (ctx.mode === this.SM4_ENCRYPT) {
			for (let i = 0; i < data.length; i += 16) {
				const ins = data.slice(i, i + 16);
				const xorBlock = ins.map((val, idx) => val ^ currentIv[idx]);
				const out = new Array(16).fill(0);
				this.sm4_one_round(ctx.sk, xorBlock, out);
				bous.push(...out);
				currentIv = out.slice();
			}
		} else {
			for (let i = 0; i < data.length; i += 16) {
				const ins = data.slice(i, i + 16);
				const out = new Array(16).fill(0);
				this.sm4_one_round(ctx.sk, ins, out);
				const decrypted = out.map((val, idx) => val ^ currentIv[idx]);
				bous.push(...decrypted);
				currentIv = ins.slice();
			}
		}

		let output = bous;
		if (ctx.isPadding && ctx.mode === this.SM4_DECRYPT) {
			output = this.padding(output, this.SM4_DECRYPT);
		}

		return output.map((v) => (v < 0 ? v + 256 : v));
	}
}

export class SM4Util {
	private secretKey: string = 'GJwsXX_BzW=gJWJW';
	private iv: string = 'ZkR_SiNoSOFT=568';
	constructor(secretKey?: string, iv?: string) {
		if (secretKey) {
			this.secretKey = secretKey;
		}
		if (iv) {
			this.iv = iv;
		}
	}

	public encryptData_ECB(plainText: string): string | null {
		try {
			const sm4 = new SM4();
			const ctx: SM4Context = { mode: sm4.SM4_ENCRYPT, isPadding: true, sk: [] };
			sm4.sm4_setkey_enc(ctx, this.stringToByte(this.secretKey));
			const encrypted = sm4.sm4_crypt_ecb(ctx, this.stringToByte(plainText));
			return base64js.fromByteArray(new Uint8Array(encrypted)).replace(/\s+/g, '');
		} catch (e) {
			console.error(e);
			return null;
		}
	}

	public decryptData_ECB(cipherText: string): string | null {
		try {
			const sm4 = new SM4();
			const ctx: SM4Context = { mode: sm4.SM4_DECRYPT, isPadding: true, sk: [] };
			sm4.sm4_setkey_dec(ctx, this.stringToByte(this.secretKey));
			const cipherBytes = Array.from(base64js.toByteArray(cipherText));
			const decrypted = sm4.sm4_crypt_ecb(ctx, cipherBytes);
			return this.byteToString(decrypted);
		} catch (e) {
			console.error(e);
			return null;
		}
	}

	public encryptData_CBC(plainText: string): string | null {
		try {
			const sm4 = new SM4();
			const ctx: SM4Context = { mode: sm4.SM4_ENCRYPT, isPadding: true, sk: [] };
			sm4.sm4_setkey_enc(ctx, this.stringToByte(this.secretKey));
			const encrypted = sm4.sm4_crypt_cbc(ctx, this.stringToByte(this.iv), this.stringToByte(plainText));
			return base64js.fromByteArray(new Uint8Array(encrypted)).replace(/\s+/g, '');
		} catch (e) {
			console.error(e);
			return null;
		}
	}

	public decryptData_CBC(cipherText: string): string | null {
		try {
			const sm4 = new SM4();
			const ctx: SM4Context = { mode: sm4.SM4_DECRYPT, isPadding: true, sk: [] };
			sm4.sm4_setkey_dec(ctx, this.stringToByte(this.secretKey));
			const cipherBytes = Array.from(base64js.toByteArray(cipherText)); // 转换为 number[]
			const decrypted = sm4.sm4_crypt_cbc(ctx, this.stringToByte(this.iv), cipherBytes);
			return this.byteToString(decrypted);
		} catch (e) {
			console.error(e);
			return null;
		}
	}

	public stringToByte(str: string): number[] {
		const bytes: number[] = [];
		for (let i = 0; i < str.length; i++) {
			const c = str.charCodeAt(i);
			if (c >= 0x010000 && c <= 0x10ffff) {
				bytes.push(((c >> 18) & 0x07) | 0xf0);
				bytes.push(((c >> 12) & 0x3f) | 0x80);
				bytes.push(((c >> 6) & 0x3f) | 0x80);
				bytes.push((c & 0x3f) | 0x80);
			} else if (c >= 0x000800 && c <= 0x00ffff) {
				bytes.push(((c >> 12) & 0x0f) | 0xe0);
				bytes.push(((c >> 6) & 0x3f) | 0x80);
				bytes.push((c & 0x3f) | 0x80);
			} else if (c >= 0x000080 && c <= 0x0007ff) {
				bytes.push(((c >> 6) & 0x1f) | 0xc0);
				bytes.push((c & 0x3f) | 0x80);
			} else {
				bytes.push(c & 0xff);
			}
		}
		return bytes;
	}

	public byteToString(arr: number[]): string {
		let str = '';
		for (let i = 0; i < arr.length; i++) {
			const one = arr[i].toString(2).padStart(8, '0');
			const v = one.match(/^1+?(?=0)/);
			if (v && one.length === 8) {
				const bytesLength = v[0].length;
				let store = one.slice(7 - bytesLength);
				for (let st = 1; st < bytesLength; st++) {
					store += arr[i + st].toString(2).padStart(8, '0').slice(2);
				}
				str += String.fromCharCode(parseInt(store, 2));
				i += bytesLength - 1;
			} else {
				str += String.fromCharCode(arr[i]);
			}
		}
		return str;
	}
}
